Age In Korea Research Articles

Abstract PO1-17-11: Trends in post-mastectomy reconstruction by age in Korea and among Asian-Americans

Abstract Background: Post-mastectomy immediate breast reconstruction (PMIBR) has been underutilized in the elderly. This study examines the trends of PMIBR by age in a large Korean medical center and compares them to the Asian-American population in the National Cancer Database (NCDB). Methods: We analyzed 5,601 patients who underwent PMIBR out of 13,654 total mastectomy patients between 2001 and 2021 in a Korean Center. Patient characteristics associated with higher likelihood of receiving reconstruction were assessed and compared between patients under 60 years of age and those aged 60 years and older. Complications were investigated in 1,669 patients between 2010 and 2020. In addition, we compared this to 966,354 female patients in the NCDB from 2004-2020 with stage 0-3 breast cancer who underwent mastectomy. Results: The number of PMIBR at the Korean center increased almost ten-fold, but there was a discrepancy in the increase between younger and older women. In the younger group, the proportion of PMIBR rose from 13% (53/398) to 77% (508/664), while in the older group, it increased from 0% (0/60) to 26% (49/186). In the NCDB, Asian-Americans had the lowest rate of breast reconstruction (29%) compared to white (35.4%), black (30.1%), and Hispanic Americans (33.5%). As seen in the table, the rates increased in both age groups but plateaued around 2014 and remained stable until 2020. In 2020, the PMIBR rates were 37% for young Asian-Americans, 48% for young non-Asians, 14% for older Asian-Americans, and 24% for older non-Asians. At the Korean center, patients living in a metropolitan area (42.6% vs.39.8% p=0.001), having higher education (44.7% vs. 10.5% p< 0.001), being unmarried (63.1% vs. 39.3% p< 0.001), having no history of childbirth (53.7% vs 39.9% p< 0.001), having lower stage and hormone receptor-positive HER2-negative breast cancer were more likely to undergo reconstruction. These factors were all more common in the younger age group. In the NCDB, patients receiving PMIBR were more likely to be white or non-Asian, have higher income and education, reside in a metropolitan area and in the Northeast, have less comorbidities, be treated in an academic center, and have a luminal subtype, lower stage, and private health insurance. At the Korean center, autologous reconstruction was more common than implant reconstruction, (68.4% vs. 31.6% for younger women, and 63.3% vs. 36.9% for older women) and the complication rate was similar for both age groups. In contrast, in the NCDB, implant reconstruction was more common in both age groups, tissue-based (29% vs 31%), implant-based (40.7% vs 40%), combined (11% vs 10.8%) and other (18% vs 17.6%) for older and younger women respectively. Conclusion: Both the Korean and American data illustrate remarkably lower utilization of immediate breast reconstruction in older patients. There are notable demographic and clinical differences between age groups but negligible difference in complication rates. Further research and interventions to address barriers in older women are needed. The higher rates of PMIBR in South Korea mirrors that of white women in the northeast USA, suggesting a potential disparity for Asian-Americans. Percentage of PMIBR over total mastectomy (with or without reconstruction) by age and race PMIBR= post-mastecomy immediate breast reconstruction; NCDB= national cancer database Citation Format: Soo-Young Lee, Madhav KC, Hyun Ho Han, Leah Kim, Mehra Golshan, Eric Schneider, Rachel Greenup, Donald Lannin, Hyung Bae Kim, Byung Ho Son, Jong Won Lee, Sae Byul Lee, Hee Jeong Kim, Tristen Park. Trends in post-mastectomy reconstruction by age in Korea and among Asian-Americans [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO1-17-11.

Analysis of Risk Factors for COPD Incidence in Adults Over 40 Years of Age in Korea

Analysis of Risk Factors for COPD Incidence in Adults Over 40 Years of Age in Korea

Association between Chronic Atrophic Gastritis and Bone Mineral Density among Women Older than 40 Years of Age in Korea.

Chronic atrophic gastritis causes hypochlorhydria, hypergastrinemia, and malabsorption of nutrients, leading to lower bone mineral density. The few studies that investigated the association between chronic atrophic gastritis and bone mineral density have reported inconsistent findings. As such, the present study assessed the association between chronic atrophic gastritis and bone mineral density among a large sample of women >40 years of age in Korea. Data from 8,748 women >40 years of age who underwent esophagogastroduodenoscopy and bone densitometry were analyzed. Chronic atrophic gastritis was diagnosed using esophagogastroduodenoscopy. Bone mineral density of the lumbar vertebrae (L), femur neck, and femur total, measured using dual-energy X-ray absorptiometry, were the primary outcome variables. Low bone mineral density, which could be diagnosed as osteoporosis or osteopenia, was defined and analyzed as a secondary outcome. Linear regression was used to calculate adjusted mean values of bone mineral density. The association between low bone mineral density and chronic atrophic gastritis was analyzed using multiple logistic regression. The adjusted mean bone mineral density for L1-L4 was 1.063±0.003, femur neck (0.826±0.002), and femur total (0.890±0.002) were significantly lower in patients with chronic atrophic gastritis than others (1.073±0.002, 0.836±0.001, 0.898±0.002, respectively; all P<0.01). Women with chronic atrophic gastritis exhibited an increased likelihood for osteopenia or osteoporosis, even after adjusting for age and other confounding factors (odds ratio, 1.25; 95% confidence interval, 1.13-1.40; P<0.01). However, subgroup analysis revealed statistical significance only in postmenopausal women (odds ratio, 1.27; P<0.001). Chronic atrophic gastritis was associated with lower bone mineral density and a higher risk for osteopenia or osteoporosis among postmenopausal women.

Genetic parameter changes and age−age correlations in Pinus koraiensis growth over 40-year progeny testing

BackgroundEarly selection in tree breeding could be achieved by addressing the longevity of tree improvement activities. Genetic parameter changes and age–age correlations are essential for determining the optimal timing of early selection. Practical tracking of genetic parameters of Pinus koraiensis, a major timber species with economic and ecological value, has become feasible as its progeny testing has entered the mid-term age in Korea. However, research on the age−age correlation of P. koraiensis as progeny trials approach rotation age is limited. This study aimed to investigate genetic parameter trends and age−age correlations in P. koraiensis progeny. P. koraiensis progeny were assessed at two sites using a linear mixed-effects model with two-dimensional spatial autoregressive structure. Height, diameter, and volume growth were measured in 11 assessments over 40 years.ResultsGenetic parameters, such as height and diameter, showed different patterns of change. The heritability ranged for the three growth traits in 0.083–0.710, 0.288–0.781, and 0.299–0.755 across the sites and age. Height heritability and its coefficient of variance decreased, whereas the diameter and volume estimates remained relatively constant. Correlations with Age 40 for phenotypic, genetic, and rank of breeding values ranged between 0.16 and 0.92, 0.594 and 0.988, and 0.412 and 0.965, respectively. These correlations generally increased as the age approached Age 40, with particularly high levels observed at Age 26 and Age 30.ConclusionThe observed genetic trends in P. koraiensis progeny testing offer valuable insights for early and precise selection. Notably, selecting superior genotypes at Ages 26–30 is supported by discernible genetic gains and robust correlations. Future research should integrate unbalanced data for selecting mother trees or families and conduct a comprehensive economic analysis of early selection to validate its practical benefits.

Disease burden of COPD attributable to PM2.5 in China, Japan and South Korea from 1990 to 2019: a comparative study based on Global Burden of Disease Study 2019

ObjectiveWe hope to reveal the changing trends of chronic obstructive pulmonary disease (COPD) burden attributable to particulate matter pollution (PM2.5) and its age, period and cohort effects in China, Japan...

Association between Dyslipidemia and Glycated Hemoglobin in a Population-Based Study.

Diabetes mellitus and dyslipidemia are well-known risk factors for cardiovascular disease. Unfortunately, the prevalence of dyslipidemia and diabetes mellitus among individuals over 30 years of age in Korea has continuously increased. The current study therefore investigated the association between dyslipidemia and high glycated hemoglobin (Hemoglobin A1c, HbA1c) levels according to age group in adults over 20 years old. We used data from the 7th Korea National Health and Nutrition Examination Survey conducted by the Korea Centers for Disease Control and Prevention from 2016 to 2017. Glycated hemoglobin, a well-established marker for elevated glucose levels, was categorized into three groups, normal (<5.7%), prediabetes (5.7-6.4%), and diabetes (≥6.5%). The presence of dyslipidemia was defined based on a diagnosis of dyslipidemia by a physician. Logistic regression analyses were performed to evaluate the association between the prevalence of dyslipidemia and glycated hemoglobin according to age group. After adjusting for possible confounders, including age, sex, body mass index, marital status, education, occupation, household income, drinking, and smoking, we found a significant increase in the odds ratios (ORs) for dyslipidemia in the prediabetes (OR; 1.915, 95% CI; 1.696 to 2.163) and diabetes (OR; 3.533, 95% CI; 3.019 to 4.134) groups. Among subjects with higher glycated hemoglobin levels, those in their 40s or over had significantly increased odds for dyslipidemia. The current study found an association between high glycated hemoglobin levels and a diagnosis of dyslipidemia among Korean adults. Markers of lipid metabolism in adults with high glycated hemoglobin levels may need to be monitored, especially those in their 40s and older.

Association between household income levels and nutritional intake of allergic children under 6 years of age in Korea: 2019 Korea National Health and Nutrition Examination Survey and application of machine learning.

This study investigated the prevalence of allergic diseases in Korean children aged 6 and below, focusing on the interplay between nutritional status, household income levels, and allergic disease occurrence. This study used data from the 2019 Korea National Health and Nutrition Examination Survey, a nationwide comprehensive survey, and included a representative sample of 30,382 children under the age of 6 to investigate in detail the relationship between allergic diseases, nutritional intake, and socioeconomic factors. Logistic regression analysis was performed to identify factors associated with allergic diseases, including gender, BMI, eating habits, dietary supplement intake, and nutrient consumption. To predict childhood asthma, 14 machine learning models were compared using the 'pycaret' package in Python. We discerned that 24.7% were diagnosed with allergic conditions like atopic dermatitis, asthma, and allergic rhinitis. Notably, household income exhibited a significant influence, with the lowest income quartile exhibiting higher prevalence rates of asthma, allergic rhinitis, and multiple allergic diseases. In contrast, the highest income quartile displayed lower rates of allergic rhinitis. Children diagnosed with allergic diseases demonstrated compromised intake of essential nutrients such as energy, dietary fiber, vitamin B1, sodium, potassium, and iron. Particularly noteworthy were the deficits in dietary fiber, vitamin A, niacin, and potassium intake among children aged 3-5 with allergies. Logistic regression analysis further elucidated that within low-income families, female children with higher BMIs, frequent dining out, dietary supplement usage, and altered consumption of vitamin B1 and iron faced an elevated risk of allergic disease diagnosis. Additionally, machine learning analysis pinpointed influential predictors for childhood asthma, encompassing BMI, household income, subjective health perception, height, and dietary habits. Our findings underscore the pronounced impact of income levels on the intricate nexus between allergic diseases and nutritional status. Furthermore, our machine learning insights illuminate the multifaceted determinants of childhood asthma, where physiological traits, socioeconomic circumstances, environmental factors, and dietary choices intertwine to shape disease prevalence. This study emphasizes the urgency of tailored nutritional interventions, particularly in socioeconomically disadvantaged populations, while also underscoring the necessity for comprehensive longitudinal investigations to unravel the intricate relationship between allergic diseases, nutritional factors, and socioeconomic strata.

Cost-Utility Analysis for Colorectal Cancer Screening According to the Initiating Age of National Cancer Screening Program in Korea.

This study aimed to identify the most cost-effective strategy for colorectal cancer screening using the fecal immunochemical test (FIT), focusing on screening initiation age in Korea. We designed Markov simulation models targeting individuals aged 40 years or older. Twelve strategies combining screening initiation ages (40, 45, or 50 years old), termination ages (80 or no limit), and intervals (1 or 2 years) were modeled, and the most cost-effective strategy was selected. The robustness of the results was confirmed using one-way and probabilistic sensitivity analyses. Furthermore, the cost-effectiveness of the qualitative and quantitative FIT methods was verified using scenario analysis. The 2-year interval strategy with a screening age range of 45-80 years was the most cost-effective (incremental cost-utility ratio = KRW 7,281,646/quality adjusted life years). The most sensitive variables in the results were transition rate from advanced adenoma to local cancer and discount rate. The uncertainty in the model was substantially low. Moreover, strategies starting at the age of 40 years were also cost-effective but considered suboptimal. The scenario analysis showed that there was no significant difference in cost-effectiveness between strategies with various relative screening ratio of quantitative and qualitative method. The screening method for advancing the initiation age, as presented in the 2015 revised national screening recommendations, was superior regarding cost-effectiveness. This study provides a new paradigm for the development of a national cancer screening system in Korea, which can be utilized as a scientific basis for economic evaluations.

Validity and Reliability of the Korean Version of the Postpartum Bonding Questionnaire (K-PBQ)

Purpose: We evaluated the validity and reliability of the Korean version of the Postpartum Bonding Questionnaire (K-PBQ) among Korean parents with children under 12 months of age.Methods: The K-PBQ was translated considering Korean cultural validity through translation, back-translation, and expert panel review. Construct validity was tested by conducting both exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) with data from 308 couples (N=616). Convergent and discriminant validity were performed using correlations between the K-PBQ and instruments measuring the concepts of attachment, postnatal depression, and dyadic adjustment. The reliability of the K-PBQ was calculated using Cronbach’s ⍺ coefficients.Results: EFA revealed that the 25-item K-PBQ was composed of two factors: impaired bonding (17 items) and the burden of infant care (8 items). The results of the final model fit were acceptable. Known-group validity showed that the K-PBQ score of the postnatal depressed group was significantly higher than that of the non-depressed group. The Cronbach’s ⍺ of the K-PBQ was .95.Conclusion: The K-PBQ was verified as a valid and reliable scale to measure postpartum bonding among parents with children under 12 months of age in Korea. It may contribute to facilitating further research on parent-infant bonding.

The impact of working hours on pregnancy intention in childbearing-age women in Korea, the country with the world's lowest fertility rate.

This study aimed to assess factors affecting pregnancy intention among women of reproductive age in Korea. We analyzed data from the Korean National Health and Nutrition Examination Survey (KNHANES), a population-based survey that included 22,731 women aged 15-49. As age was associated with birth year and was found to be a confounding factor in the analysis of participants' characteristics, we used propensity score matching to assess the characteristics of pregnant women compared with non-pregnant women of the same age and birth year. We also employed the XGBoost machine learning model to identify the most important factors related to pregnancy intentions. Our feature importance analysis showed that weekly working hours were the most significant factor affecting pregnancy intentions. Additionally, we performed cluster analysis and logistic regression models to determine optimal weekly working hours. Cluster analysis identified participants into three distinct groups based on their characteristics, indicating that the group with an average of 34.4±12.9 hours per week had the highest likelihood of becoming pregnant. Logistic regression was used to analyze the odds of pregnancy for every 5-hour increase in weekly working hours. The results of logistic regression indicated that women who worked between 35-45 hours per week had higher odds of pregnancy, with significant odds ratios of 2.009 (95% confidence interval: 1.581-2.547, p < .001) for 40-45 hours per week and 1.450 (95% confidence interval: 1.001-2.040, p < .05) for 35-40 hours per week, compared to women working other hours. In Korea, the standard workweek is typically 40 hours; however, Koreans often work considerably longer hours, with the second-highest number of working hours among OECD countries in 2022. This study suggests that strict monitoring of working hours and expansion of telecommuting for childbearing-age women are important factors in increasing the fertility rate in Korea.

Psychosocial factors associated with health behaviors in pregnant women of advanced maternal age in Korea.

To determine the association between psychosocial factors and health-promoting and health-impairing behaviors in pregnant women of advanced maternal age (AMA) in Korea. A cross-sectional survey study. Online survey. A total of 217 pregnant women aged 35 and older agreed to participate in the study, with 207 participants completing the self-report questionnaires. We collected self-reported data on demographic, obstetric, and psychosocial factors and prenatal health behaviors using standardized measures. We conducted a descriptive analysis of the collected data and a linear regression to identify significant associations with health-promoting and health-impairing behaviors. We found that maternal-fetal attachment (β = 0.43, p < 0.001) and "social atmosphere" of pregnancy stress (β = 0.13, p = 0.047) were positively associated with prenatal health-promoting behaviors. We found that artificial conception (β =-0.16, p = 0.011) was negatively associated with prenatal health-impairing behaviors and that multiparity (β = 0.23, p = 0.001) and "maternal role" of pregnancy stress (β = 0.27, p = 0.003) positively associated with prenatal health-impairing behaviors. Health-impairing behaviors of pregnant AMA women need assessment and the importance of health-promoting behaviors for maternal and infant health need reinforcing. We recommend pregnancy stress assessments at prenatal checkups and stress relief interventions that consider cultural differences and contexts rather than standardized interventions.

Corrigendum: Educational Status and Needs of Premature Birth Prevention and Its Association with Preconception Health Behavior among Women of Childbearing Age in Korea

Corrigendum: Educational Status and Needs of Premature Birth Prevention and Its Association with Preconception Health Behavior among Women of Childbearing Age in Korea

Effects of once-weekly dulaglutide on juvenile type 2 diabetes mellitus and obesity in Korea: a pilot study.

We sought to investigate the effects and side effects of once-weekly dulaglutide treatment for type 2 diabetes mellitus (T2DM) in patients <18 years of age in Korea. : From the Eulji University Hospital database, we identified all patients <18 years of age diagnosed with T2DM and treated with dulaglutide from January 1, 2017, to July 31, 2022. We identified 5 patients <18 years of age treated with dulaglutide for T2DM management. Their mean (standard deviation [SD]) age was 16.6 (0.5) years. Four (80%) patients were female. The mean (SD) body mass index was 29.4 (5.1) kg/m2, and the mean (SD) age at diagnosis was 15.2 (1.6) years. Four patients had been treated previously with metformin alone or in combination with insulin. Four patients were treated with 1.5 mg of dulaglutide and one was treated with 0.75 mg of dulaglutide. The mean (SD) hemoglobin A1c concentrations at baseline, 3 months after treatment, and 1 year after treatment, respectively, were 10.0% (2.2%), 6.5% (1.5%), and 6.7% (1.4%), with significant differences. In addition, at baseline, 3 months after treatment, and 1 year after treatment, the mean (SD) body weight values were 79.7 (13.3) kg, 80.2 (14.0) kg, and 81.1 (15.3) kg, with no significant difference. Use of once-weekly dulaglutide for juvenile T2DM ensures very good glycemic control, with few side effects and good adherence, indicating its potential as a promising therapeutic agent in this age group. Nationwide studies are warranted to confirm our results.

Relationship between remaining teeth and mental health indicators in adults over 50 years of age in Korea

Relationship between remaining teeth and mental health indicators in adults over 50 years of age in Korea

Korean Chronicles Under a Macroscope: Towards a Digital Infrastructure in Premodern Korean Studies

Abstract: Starting in the 1990s, digital humanists have endeavored to create the "macroscope," a holistic research environment that allows for a flexible, multiscalar reading of large text corpora. Many macroscopes have since emerged, from fields as diverse as Danish folklore studies, English literary studies, and Chinese biographical studies. But in creating Silloker, we are the first to offer a "historian's macroscope" for premodern Korean chronicles. Silloker is a digital platform that opens creative avenues into studying Korea's Chosŏn dynasty (1392–1910). Its title takes after Chosŏn wangjo sillok ("Veritable Records of the Chosŏn Dynasty" 朝鮮王朝實錄), court annals that cover five centuries and topics as varied as diplomacy, economy, religion, quotidian life, and natural phenomena. For this archive and others—for example, Diaries of the Royal Secretariat 承政院日記 ( Sŭngjŏngwŏn ilgi ), Records of the Border Defense Council 備邊司謄錄 ( Pibyŏnsa tŭngnok )—our platform features new search capacities and tools for exploratory data analysis. First, it allows users to make unified queries across multiple archives and download the search results. Second, it offers a tool for aggregating and graphing the frequency of search hits throughout the five-centuries long dynasty, generating real-time results in table and graph. This essay introduces Silloker, its functionalities, and data architecture. It then provides an example case study of the Little Ice Age in Korea to demonstrate the platform's utility for historical research.

국내 한국사학계의 환경·기후 문제 연구 동향과 과제

With emphasis on the question of why the 1600s and 1700s, well known as the age of chronic natural disasters caused by the Little Ice Age in Korean history, did not witness a decrease in population or a steady decline in the rate of population growth but rather underwent a rapid increase of population, this review article examines the preexisting studies that employed the Little Ice Age theory to explain the socioeconomic crisis in the late Joseon dynasty. In a premodern society, population growth is generally a byproduct of either a long-term increase in agricultural productivity or a steady influx of wealth through international trade. When such an economic growth is prolonged, a sort of population pressure takes place. If a society fails to breakthrough population pressure with either a new economic power or a new land for outmigration, it could stop economic growing or fall into poverty as we can see the case of nineteenth-century Qing China. During the so-called Little Ice Age in Korea, covering from the turn of the 1600s to the mid-1700s, let alone China and Japan, population grew remarkably in spite of chronic natural disaster and great famine, suggesting that the impact of the Little Ice Age on Korean society in a long term view was somewhat exaggerated. In this review article I challenge the current uses of the Little Ice Age theory in Korean academia of history.

2149. Risk of dental abnormalities after tetracycline exposure in children: A retrospective, population-based study in Korea, 2003-2015

Abstract Background Despite its clinical usefulness, the use of tetracycline antibiotics (TCs) in children has historically been limited because of the risk of permanent tooth discoloration and enamel deformity, although age restrictions have varied across countries (e.g., contraindicated under 8 years of age in Taiwan, USA, and Canada, and under 12 years of age in Korea and UK). We explored whether the incidence of dental abnormalities in Korean children with a history of TCs use differed by age. Furthermore, the relative risk compared to the TCs non-exposed group was calculated. Methods From 2002 to 2015, 1 million standard sample subjects data was provided from National Health Insurance Service in Korea. Children younger than 18 years were included and divided into groups A (0-7 years), B (8-12 years), and C (13-17 years). Subjects in 2002 were excluded for wash-out, as were those diagnosed with dental abnormalities within 6 months after TCs prescription. For comparison, 1:4 matching between the TCs exposure and non-exposure groups was performed according to age and gender. Results Among 14,831 individuals included as study subjects (487 (3%) in group A; 1,695 (11%) in group B; and 12,649 (85%) in group C), 201 (1.4%) were diagnosed with dental abnormalities. The 5-year cumulative incidence of dental abnormalities after exposure to TCs in the group A was 4.7%, which was significantly higher than that of the control group C (0.9%; p&amp;lt; 0.0001), but that of group B was 1.3% and not significantly different from that of group C. In the risk analysis of dental abnormalities according to exposure of TCs, there was no significant difference (adjusted RR=1.03, 95%CI=0.71 to 1.50 in group A; adjusted RR=1.13, 95%CI=0.76 to 1.69 in group B; adjusted RR=1.18, 95%CI=0.97 to 1.43 in group C). Fig 1.Cumulative incidence rate and relative risk analysis.A. Cumulative incidence rate of dental abnormalities after TCs exposure by age group (p = &amp;lt;.00001). B. Relative risk analysis by TCs exposure and age group.Abbreviation; TCs: tetracycline and its derivatives. Conclusion Korean children aged 0-7 years who were exposed to TCs had a higher cumulative incidence and relative risk of dental deformities compared to the 13-17-year-old group but not the 8-12-year-old group. No significant increase in dental abnormalities was observed with TCs exposure among pediatric age groups. Disclosures All Authors: No reported disclosures.

Association between Stress Perception and Physical Activity in Elderly

Purpose: The purpose of this study was to investigate the relationship of stress perception and physical activity in the elderly over 60 years of age in Korea. Methods: This s tudy was a s econdary d ata analysis and used d ata from the 8 th 2 nd ( 2 02 0) National Health and Nutrition Examination Survey (KNHANES) as raw data. The subjects of this study were 2,360 elderly people aged 60 years or older from raw data. Data analysis was performed using IBM SPSS 25 ver. Descriptive statistics, chi-square analysis and complex sample logistic regression analysis were performed. Results: Household income, women, subjective health perception, walking were related to stress perception. In result of complex sample logistic regression analysis after adjusting the control variables, the stress perception in 60-69 ages was 2.064 times higher in the case of '1-2 days' walking per week compared to 'more than 3 days' walking per week. The stress perception in 70 years and older was 1.801 times higher in the case of 'none' walking per week compared to 'more than 3 days walking per week. Conclusion: The results provide a basis information for developing an intervention program to improve the stress management and develop a program for healthy aging.

Urinary phthalate metabolites and phenolics in women of childbearing age and their association with thyroid hormones: a comparison study of fasting status

[BACKGROUND AND AIM] Exposure to parabens and phthalates has been associated with thyroid hormones in humans. Epidemiologic observations, however, are often inconsistent depending on population, probably due to different susceptibility or other factors such as exposure misclassification. Fasting status may influence the urinary levels of many chemicals, especially when their major exposure pathways are related to diet. In the present study, we assessed the associations of urinary phthalate metabolites and phenolics with thyroid hormones in non-pregnant women of child-bearing age in Korea (20-49 years of age), considering fasting status. [METHODS] As a fasting population, we recruited women (n=254) who visited four hospitals after &amp;#x3e;9 hr of fasting between 2015 and 2016. From the fasting women, we measured phthalate metabolites and parabens in urine, and thyroid hormones in serum. Non-pregnant women of the same age group, who were not asked to fast, was chosen from KoNEHS Cycle 3 (2015-2017) (phthalate metabolites (n=341) and phenolics (n=340)). [RESULTS] Urinary concentrations of MEHHP, MEOHP, MBzP, and BPA were &amp;#x3e;2 folds higher in the non-fasting women, and those of MeP were higher in the fasting women. Regardless of fasting status, MeP and EtP levels showed significant negative association with both total and free T4. DEHP metabolites also showed negative associations with free T4 but positive associations with total T3. However, associations of MBzP and BPA with thyroid hormones varied by the fasting status, which might be due to the influence of diet on their urinary concentrations. [CONCLUSION] While certain chemicals like EtP and to lesser extent DEHP are known to be delivered through dietary factors, consistent associations with altered thyroid hormones regardless of fasting status are noteworthy. [KEYWORDS] thyroid hormones; fasting; phthalates; phenolics [Acknowledgement] This work was supported by grants from National Research Foundation of Korea (NRF) (NRF-2020R1A2C3011269 and NRF-2022R1C1C2006982).

Effects of Frequent Smartphone Use on Sleep Problems in Children under 7 Years of Age in Korea: A 4-Year Longitudinal Study.

The use of electronic screen devices has a negative effect on sleep. The purpose of this study is to longitudinally examine the effects of various screen use on sleep problems in children under 7 years of age. A total of 314 caregivers of children aged 4–7 years from three cities in Korea were recruited and responded to a self-administered questionnaire from 2017 to 2020. As a result of the analysis of the mixed model designed as a two-leveled structure, the use frequency of smartphones significantly predicted children’s sleep problems (β = 0.328, p < 0.001) compared to that of TV, PC, and tablet PC. In addition, the frequency of smartphone screen use showed a weak but significant correlation with bedtime resistance (r = 0.067, p = 0.009), sleep duration (r = 0.089, p <0.001), nighttime awakening (r = 0.066, p = 0.010), and daytime sleepiness (r = 0.102, p < 0.001). The results of this study suggest that screen time education in Korea should focus on smartphones above all else.